I thought you make use of the "tools" previously and build your new system manually. If you are using jhalfs, why not start it up from scratch?
You own a much better CPU than I do and I can image you should have more RAM than I do as well.
I don't use VM and am not familiar with it. I have a Sempron-64 3000+ and 1.5G RAM. With jhalfs, it completed the build of LFS-6.3 within 1.5hrs. That's already 3 years ago.